127 research outputs found
Development of Methods to Evaluate Several Levels of Uranium Concentrations in Drainage Water Using Total Reflection X-Ray Fluorescence Technique
As a country's law stipulates the effluent standard uranium concentration in drainage water, the uranium concentration must be determined when drainage water is released from a uranium handling facility, such as the Fukushima Daiichi nuclear power plant. The maximum allowable limit for uranium release at each facility is defined taking into consideration the situation of the facility, such as 1/10 to 1/100 of this effluent standard value. Currently, the uranium concentration of drainage water is commonly determined by α-particle spectrometry, in which several liters of drainage water must be evaporated, requiring about half of a day followed by 2–3 h of measurements, due to the low specific radioactivity of uranium. This work proposes a new methodology for the rapid and simple measurement of several levels of uranium in drainage water by a total reflection X-ray fluorescence (TXRF) analysis. Using a portable device for TXRF measurements was found to enable measurements with 1/10 the sensitivity of the effluent standard value by 10 times condensation of the uranium-containing sample solution; a benchtop device is useful to measure uranium concentrations <1/100 of the effluent standard value. Therefore, the selective usage of methods by a portable and benchtop devices allows for screening and precise evaluation of uranium concentrations in drainage water
Direct Damage to a Vertebral Artery Better Predicts a Vertebral Artery Injury than Elongation in Cervical Spine Dislocation
Cervical spine dislocation and fracture of a transverse process are isolated risk factors for vertebral artery injuries (VAIs), which can cause a life-threatening ischemic stroke. Since in vivo experiments are not possible, it has not been unclear whether damage to or extension of vertebral arteries is more predictive of a VAI. To identify the imaging characteristics associated with VAI, we analyzed 36 vertebral arteries from 22 cervical spine dislocation patients who underwent computed tomography angiography (Aug. 2008-Dec. 2014). We evaluated (1) the posttraumatic elongation of the vertebral artery and (2) the presence of fracture involving the transverse foramen. VAI was found in 20 (56%) of the 36 vertebral arteries. The rate of residual shift (vertebral artery elongation) was not markedly different between the VAI and no-VAI groups. However, the rate of >1 mm displacement into the foramen and that of fracture with gross displacement (≥2 mm) differed significantly between the groups. We found that greater displacement of fractured transverse processes with cervical spine dislocation was a risk factor for VAI. These results suggest that direct damage to the vertebral arteries by transverse process fragments is more likely to predict a VAI compared to elongation, even in cervical spine dislocation
High glucose level and angiotensin II type 1 receptor stimulation synergistically amplify oxidative stress in renal mesangial cells
Abstract Oxidative stress in renal mesangial cell causes diabetic glomerular changes. High glucose levels and angiotensin II (Ang II) are known to stimulate superoxide production in renal mesangial cells. However, it has been unclear whether Ang II stimulation and pre-conditioning with high glucose affects the same pathway of superoxide production in renal mesangial cells or not. In this study, we examined the levels of oxidative stress under Ang II stimulation in renal mesangial cells preincubated for six hours at various glucose levels. Intracellular levels of reactive oxidative species (ROS) were measured using dihydroethidium or 5′,6′-chloromethyl- 2′,7′ dichlorodihydro-fluorescein diacetate, which facilitates the detection of intracellular ROS under real-time fluorescent microscope. Ang II-induced elevated intracellular ROS levels were detected only when the cells were pre-incubated with high levels of glucose (13.5 mM, 27.8 mM), but was not detected under normal glucose condition (5.5 mM). Production of Ang II-induced intracellular ROS was higher under pre-treatment with 27.8 mM glucose compared to pretreatment with 13.5 mM glucose level. This ROS production in mesangial cells was induced within several minutes of the initiation of Ang II stimulation under high glucose levels. The production of intracellular ROS was significantly reduced in the presence of angiotensin II type1-receptor (AT1R) antagonist, whereas it was augmented in the presence of angiotensin II type2-receptor antagonist. In conclusion, Ang II-induced oxidative stress was augmented by high glucose levels and ROS levels were further alleviated in the presence of AT1R antagonists
A Sensor Network to Estimate Fish Activity and Assist Feeding Decisions in Marine Aquaculture
Optimization of fish feeding in marine aquaculture has relied on an expert farmer’s decision-making based on subjective experience. This paper presents the development of a network of underwater current, imaging and IMU sensors for estimating fish feeding behavior for digitizing expert feeding decision-making. We constructed the sensor units and deployed them in fish cages and collected measurements during feeding activities. Experiment results indicate that currents were highest at the surface within the duration of the feeding activity.The 2022 International Conference on Artificial Life and Robotics (ICAROB 2022), January 20-23, 2022, on line, Oita, Japa
Histomorphometric analysis of minimodeling in the vertebrae in postmenopausal patients treated with anti-osteoporotic agents
AbstractMinimodeling is a type of focal bone formation that is characterized by the lack of precedent bone erosion by osteoclasts. Although this form of bone formation has been described for more than a decade, how anti-osteoporotic agents that are currently used in clinical practice affect the kinetics of minimodeling is not fully understood. We performed a bone morphometric analysis using human vertebral specimens collected from postmenopausal patients who underwent spinal surgery. Patients were divided into three groups according to osteoporosis medication; non-treated, Eldecalcitol (ELD, a vitamin D derivative that has recently been approved to treat patients with osteoporosis in Japan)-treated, and bisphosphonate-treated groups. Five to six patients were enrolled in each group. There was a trend toward enhanced minimodeling in ELD-treated patients and suppressed of it in bisphosphonate-treated patients compared with untreated patients. The differences of minimodeling activity between ELD-treated and bisphosphonate-treated patients were statistically significant. The present study suggests that ELD and bisphosphonates have opposite effects on minimodeling from one another, and show that minimodeling also takes place in vertebrae as has been described for the ilium and femoral head in humans
Autonomous Underwater Vehicle with Vision-based Navigation System for Underwater Robot Competition
The underwater robot competition in international conference Techno-Ocean 2021 was held to advance underwater technology, in Dec. 2021. The competition consists of five leagues including AUV (Autonomous Underwater Vehicle) league, and Kyushu underwater robotics which is the Underwater Student Project team at our university that joint the AUV league using developed AUV. The wet test of the AUV league includes a Gate Pass mission which requires passing through an underwater green gate, Buoy Touch mission requiring contact with the yellow and red buoys, and Special mission requiring contact with the Pinger which has an unknown location. Our AUV navigates by image processing using underwater camera to achieve the mission. This paper explains the AUV system, the mission strategy and detail of image processing.The 2022 International Conference on Artificial Life and Robotics (ICAROB 2022), January 20-23, 2022, on line, Oita, Japa
Severe progressive scoliosis due to huge subcutaneous cavernous hemangioma: A case report
Cavernous hemangioma consists mainly of congenital vascular malformations present before birth and gradually increasing in size with skeletal growth. A small number of patients with cavernous hemangioma develop scoliosis, and surgical treatment for the scoliosis in such cases has not been reported to date. Here we report a 12-year-old male patient with severe progressive scoliosis due to a huge subcutaneous cavernous hemangioma, who underwent posterior correction and fusion surgery. Upon referral to our department, radiographs revealed a scoliosis of 85° at T6-L1 and a kyphosis of 58° at T4-T10. CT and MR images revealed a huge hemangioma extending from the subcutaneous region to the paraspinal muscles and the retroperitoneal space and invading the spinal canal. Posterior correction and fusion surgery using pedicle screws between T2 and L3 were performed. Massive hemorrhage from the hemangioma occurred during the surgery, with intraoperative blood loss reaching 2800 ml. The scoliosis was corrected to 59°, and the kyphosis to 45° after surgery. Seven hours after surgery, the patient suffered from hypovolemic shock and disseminated intravascular coagulation due to postoperative hemorrhage from the hemangioma. The patient developed sensory and conduction aphasia caused by cerebral hypoxia during the shock on the day of the surgery. At present, two years after the surgery, although the patient has completely recovered from the aphasia. This case illustrates that, in correction surgery for scoliosis due to huge subcutaneous cavernous hemangioma, intraoperative and postoperative intensive care for hemodynamics should be performed, since massive hemorrhage can occur during the postoperative period as well as the intraoperative period
Simulation of livestock biomass resource recycling and energy utilization model based on dry type methane fermentation system
International Conference of Biomass and Bioenergy 19-20 August 2019, West Java, IndonesiaThis study was aimed at investigating the local livestock biomass volume for dairy farms in Town A, located in eastern Hokkaido, Japan, and at presenting a model of a biogas plant that enables maximizing the use of the available livestock biomass. Using a dairy farm with 250 animals in Town A as a model for a biogas plant based on dry-type methane fermentation system (dry-type biogas plant), we set the operational conditions to an average hydraulic retention time of 20 days, digestion temperature of 55°C, and methane gas yield of 0.12 Nm3 CH4/kg VSA. We compared the biogas production of our presented model with that of a wet-type biogas plant with the same number of animals. The results showed that the dry-type biogas plant produced biogas at 859 Nm3/day, while the wet-type biogas plant produced biogas at 666 Nm3/day. These results indicate that introducing dry-type biogas plants in all dairy farms in Town A would potentially enable semi-solid livestock manure to be processed, which is not amenable to ordinary composting, in addition to the conventional processes being carried out through biogas plants, as well as lead to an increase in the amount of biogas production
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